Extraction of metals

Question 1

what does the earth crust contain

Answer 1

metals and metal compounds
eg. gold, copper, iron oxide, aluminum oxide

Question 2

what are ores

Answer 2

metals which are chemically combined with other substances

Question 3

what are ways metal can be extracted

Answer 3

• electrolysis
• using a blast furnace
• reacting a metal with a more reactive one

Question 4

iron ore is called

Answer 4

haematite

Question 5

aluminium ore is called

Answer 5

bauxite

Question 6

what is found as an uncombined element

Answer 6

unreactive metal

Question 7

why are unreactive metals found as uncombined elements

Answer 7

do not react easily with other substances

Question 8

what do more reactive metals have to be extracted by

Answer 8

electrolysis

Question 9

why do higher placed metals have to be extracted by electrolysis

Answer 9

they are too reactive and cannot be reduced by carbon

Question 10

how are lower placed metals extracted

Answer 10

by heating with carbon which reduces them

Question 11

uses of aluminum

Answer 11

aeroplane body
overhead power cables
saucepans
food cans
window frames

Question 12

uses of copper

Answer 12

electrical wires
water pipes

Question 13

4 types of steel

Answer 13

mild steel
high carbon steel
low alloy steel
stainless steel

Question 14

main uses of steel

Answer 14

car body
tools
construction bridges
cutlery and sinks

Question 15

Alloys definition

Answer 15

they are a mixture of metals that are mixed together physically and are not physically combined

Question 16

physical properties of alloys

Answer 16

• greater strength and hardness
• greater resistance to corrosion and extreme temperatures

Question 17

why are alloys harder than pure metals

Answer 17

they have atoms of difference sizes (irregular arrangement) so it is more difficult for layers to slide over each other.